JP4561733B2 - Fuel shut-off valve - Google Patents

Description

  The present invention relates to a fuel cutoff valve that is attached to an upper part of a fuel tank and that opens and closes a connection passage that connects the inside and outside of the fuel tank to cut off communication between the fuel tank and the outside.

  2. Description of the Related Art Conventionally, a saddle type fuel tank is known as a fuel tank for securing shafts, exhausts, and the like and a large vehicle space (Patent Document 1). In other words, the fuel tank has a shape that includes a space that is disposed on both sides and is filled with fuel, and a connecting space that connects the two spaces in an arch shape. The propeller shaft and exhaust are located in a recessed space below the central connecting space. Pipes are arranged. When installing a full tank control valve (fuel shutoff valve) that regulates the fuel tank full tank level in such a fuel tank, install the full tank control valve on the wall at the high position of the fuel tank, A bent introduction pipe is integrally formed and bent at the lower part of the casing forming the. The full tank control valve closes the external passage by raising the float pressure and raising the float when the fuel level in the fuel filling space on both sides reaches the specified level and the opening of the inlet pipe is closed when refueling. It operates by. However, in Patent Document 1, the introduction pipe is integrally formed from the lower part of the casing, and there is a problem that the molding becomes complicated due to die cutting or the like at the time of injection molding.

JP2002-2314

  In view of solving the above-described problems of the conventional technique, the present invention provides a fuel shut-off that allows a simple configuration and a reliable assembly of a bent tube to the casing in a configuration in which fuel is introduced into the valve chamber of the casing through the bent tube. The purpose is to provide a valve.

The present invention made to solve the problems
A fuel shut-off valve that is mounted on the upper part of the fuel tank and that opens and closes a connection passage that connects the inside and outside of the fuel tank to cut off the communication between the fuel tank and the external passage.
A casing body that forms a valve chamber that connects the connection passage and the inside of the fuel tank, and an introduction opening that is provided at a lower portion of the casing body and that introduces fuel from the fuel tank, and that leads from the introduction opening to the valve chamber. A casing with a bent tube;
A float mechanism that is housed in the valve chamber and has a valve portion that raises and lowers buoyancy according to the fuel level in the valve chamber and opens and closes the connection passage;
And when the fuel level reaches a fuel level that closes the introduction opening, the fuel is guided to the valve chamber through the bent tube, and the float is raised to close the connection passage,
The bent pipe is disposed at a lower portion of the casing body obliquely downward with respect to the vertical direction and connected to the valve chamber; an introduction pipe connected to the connection pipe and having the introduction opening; A connection mechanism for connecting the connecting pipe and the introduction pipe,
The connection mechanism includes a fitting mechanism having a connection portion formed at an outer peripheral end portion of the connection pipe, and a connected portion formed at an end portion of the introduction pipe and externally fitted to the connection portion, and the connection An engagement mechanism that is formed in the tube and the connected portion and engages each other to connect the connecting tube and the connected portion, and between the outer peripheral portion of the connecting portion and the inner peripheral portion of the connecting portion And a sealing member interposed in the
The fitting mechanism includes a positioning step portion that is formed in the connected portion and positions the connection tip surface of the connection portion by contacting the tip, and a plane passing through the connection tip surface and the positioning step portion is the introduction portion. It is non-orthogonal to the axis of the tube, and the engagement mechanism is configured to be engageable when the connection tip surface and the positioning step portion are parallel to each other.

  When fuel is supplied to a fuel tank using the fuel shut-off valve according to the present invention and reaches a fuel level that closes the introduction opening, the tank internal pressure in the fuel tank is increased and the pressure difference between the tank internal pressure and the valve chamber is increased. Thus, the connection passage is closed at the valve portion by raising the float mechanism to the raised position by the fuel flowing into the valve chamber. At this time, an automatic stop for stopping the fuel supply of the fuel gun can be activated by detecting the increase in the tank internal pressure by the sensor or detecting that the fuel in the filler pipe has reached the fuel gun.

  In addition, since the bent pipe is divided into a connecting pipe and an introduction pipe, a molding die for injection molding can be simplified. Moreover, if the connected portion is inserted toward the connecting portion with the introduction opening of the introducing tube facing downward, the connected portion is fitted into the connecting portion, and the connecting tube is connected to the connecting tube by the engagement of the engaging mechanism. Can be easily connected to. At this time, the plane where the connection tip of the connecting portion contacts the positioning step of the connected portion is non-orthogonal to the axis of the introduction tube, so when the introduction tube is inserted in the wrong direction with respect to the connection portion The engagement mechanism is not engaged. Therefore, the introduction pipe is not assembled in the wrong direction to the connecting pipe, and there is no poor setting of the full tank liquid level due to incorrect installation.

  As a preferred aspect of the present invention, the outer peripheral portion of the connection portion includes a connection tip portion, a seal recess for holding the seal member, and a connection enlarged portion having an outer diameter larger than the connection tip portion. The connecting portion can be configured such that the tip of the connected portion has an outer diameter wider than the sealing surface of the seal member. With this configuration, the connected portion is formed so as to expand, and the inner diameter of the tip side is larger than the outer diameter of the seal member. Therefore, when the connected portion is inserted into the connecting portion, the inner wall of the connected portion is sealed. The member is not rubbed with a strong force, and thus the seal member is not damaged, so that the sealing performance is not deteriorated. In addition, the connection enlarged diameter part of the connection part lengthens the distance in the axial direction from the seal member to the inner wall on the tip side of the connected part, so the connected part fits firmly to the connecting pipe. In addition, tilt and backlash can be reduced. Therefore, the fluctuation of the position of the introduction opening due to the backlash of the introduction pipe is eliminated, and a stable full liquid level can be obtained.

  Moreover, as another aspect, it can be set as the structure which diameter-expands gradually as the said to-be-connected part goes to the front-end | tip of this to-be-connected part. Further, the connected portion includes a straight pipe portion having an inner wall of the same outer diameter that presses and seals the seal member, and an expansion pipe having an enlarged diameter from the straight pipe portion toward the distal end side of the connected portion. It is possible to take the configuration provided. With this configuration, the inner wall of the straight pipe portion uniformly presses the sealing member, so that the sealing performance is not deteriorated.

  Furthermore, as a preferable aspect of the present invention, a part of the outer peripheral portion of the connection portion is made small in diameter so as not to contact the inner wall of the connected portion between the connection enlarged diameter portion and the seal recess. The structure in which the annular recess is formed can be taken. The connection enlarged-diameter portion of the connection portion is provided at a position that increases the axial distance from the seal member, but even if the fitting size of the connection tip portion and the connection enlarged-diameter portion and the connected portion is reduced. Since the contact area with the inner wall of the connected part is reduced by the annular recess, the connected part can be easily fitted to the connecting part, and the connection enlarged diameter part and the connecting tip part are continuously connected. Sinks that tend to occur when formed can be prevented.

  In order to further clarify the configuration and operation of the present invention described above, preferred embodiments of the present invention will be described below.

(1) Schematic configuration of fuel cutoff valve 10 FIG. 1 is a cross-sectional view showing a fuel tank of an automobile equipped with a fuel cutoff valve 10 according to an embodiment of the present invention. In FIG. 1, the fuel tank FT has a shape inclined from the rear of the vehicle (above the tire housing) to the lower side of the floor in front of the vehicle, that is, from the high position to the bottom, and the high position of the rear part. The tank space FTSb arranged below the front floor is connected by the connection space FTSc from the tank space FTSa arranged in FIG. FIG. 2 is an enlarged cross-sectional view of the vicinity of the fuel cutoff valve 10 of FIG. The surface of the fuel tank FT is made of a composite resin material containing polyethylene, and a mounting hole FTb is formed in the tank upper wall FTa. A fuel shut-off valve 10 is attached to the tank upper wall FTa in a state where the lower part thereof enters the attachment hole FTb. The fuel shut-off valve 10 controls the outflow to the canister when the fuel in the fuel tank FT rises to a predetermined liquid level FL1 during refueling and functions an automatic stop.

(2) Configuration of Each Part of Fuel Shutoff Valve 10 The fuel shutoff valve 10 includes a casing 20, a float mechanism 60, and a spring 70 as main components, which are formed from a resin such as polyethylene, polyamide, or polyacetal. ing. FIG. 3 is an exploded cross-sectional view of the fuel cutoff valve 10. The casing 20 includes a casing body 30, a case lower support body 40, a case upper lid 45, and a lid body 50, and a space surrounded by the casing body 30 and the case upper lid 45 becomes the valve chamber 20S. The float mechanism 60 is accommodated in the valve chamber 20S. The float mechanism 60 is supported by the spring 70.

The casing body 30 is formed by a cylindrical side wall portion 31 and a bent tube 32 provided at a lower portion of the side wall portion 31. A flange 31 a for welding to the lid 50 is formed on the upper portion of the side wall portion 31. The bent pipe 32 connects the connecting pipe 33 connected to the valve chamber 20 </ b> S integrally formed in the lower part of the casing body 30, the introducing pipe 34 connected to the connecting pipe 33, and the connecting pipe 33 and the introducing pipe 34. And a connection mechanism 35. FIG. 4 is an enlarged cross-sectional view of the vicinity of the bent tube 32. The connecting pipe 33 is formed at the lower portion of the casing body 30 and is gradually reduced in diameter, the vertical portion 33b formed at the lower portion of the reduced diameter portion 33a, and the slope formed at the lower portion of the vertical portion 33b. Part 33c. The inclined portion 33c is disposed obliquely downward with respect to the vertical direction from the vertical portion 33b. The introduction tube 34 integrally forms a tube body 34a and a bent tube 34b bent in the vertical direction from the tube body 34a, and the opening of the bent tube 34b is an introduction opening 34c. The introduction opening 34c is set to a predetermined liquid level FL1 (see FIG. 2) that determines the full tank liquid level of the fuel tank FT.
The connection mechanism 35 includes a fitting mechanism 36 that fits the end portions of the connection pipe 33 and the introduction pipe 34, and an engagement mechanism 39 that engages the connection pipe 33 and the introduction pipe 34. The fitting mechanism 36 has a connection portion 37 formed at the outer peripheral end portion of the connecting pipe 33 and a connected portion 38 formed at the end portion of the introduction pipe 34 and fitted around the connection portion 37.

  FIG. 5 is an enlarged cross-sectional view of the vicinity of the connection mechanism 35 of FIG. The connecting portion 37 is configured by sequentially arranging a connecting tip portion 37a, a seal recess portion 37b, an annular recess portion 37c, and a connection enlarged diameter portion 37d from the connecting tip end surface 37e. Out of the connecting tip 37a, the outer peripheral portion on the side of the connection enlarged portion 37d from the seal recess 37b and the connection enlarged portion 37d are formed on a tapered surface that is gradually enlarged in diameter. Further, the seal recess 37b holds a seal member SP made of an O-ring. The annular recess 37c is formed between the connection tip portion 37a and the connection enlarged diameter portion 37d. Further, the connection enlarged diameter portion 37d is formed to have a larger diameter and a taper shape than the connection distal end portion 37a, that is, the outer diameter of the connection distal end portion 37a is D1, and the outer diameter of the connection enlarged diameter portion 37d is D2. D2> D1. The connected portion 38 is expanded in diameter so as to be fitted to the connecting portion 37, that is, a positioning step 38a and a step 38b are formed between the connected portion 38 and the pipe body 34a. The positioning step portion 38a regulates the amount of insertion of the connected portion 38 into the connecting portion 37 when the connecting tip end surface 37e of the connecting portion 37 hits. Further, the positioning step portion 38a is disposed on the vertical plane, and since the introduction pipe 34 is inclined, it is not orthogonal to the axis of the introduction pipe 34. In addition, a straight pipe portion 38c is formed between the positioning step portion 38a and the step 38b, and an expansion tube 38d having a gradually increasing outer diameter is formed between the step 38b and the tip of the connected portion 38. ing. The straight pipe portion 38c has the same inner diameter in order to apply an equal pressing force to the seal member SP, while the expansion pipe 38d is directed toward the tip in consideration of the insertability into the connection portion 37. The outer diameter is gradually increased.

  FIG. 6 is a side view showing the vicinity of the engaging mechanism 39 of the bent tube 32. FIG. 7 is a cross-sectional view taken along line 7-7 in FIG. The engaging mechanism 39 includes an engaging claw 39 a protruding from the outer peripheral wall on both sides of the connecting pipe 33, and an engaging piece 39 b protruding in the axial direction from the end of the connected portion 38 and having an engaging hole 39 c. When the engaging hole 39c is engaged with the engaging claw 39a, the connected portion 38 prevents the connecting portion 37 from being pulled out.

  In order to connect the introduction pipe 34 to the connection pipe 33, as shown in FIGS. 4 and 5, the seal member SP is set in advance in the seal recess 37b of the connection pipe 33 and the introduction opening 34c is directed downward to be connected. The part 38 is inserted toward the connection part 37. At this time, the inner wall of the connected portion 38 passes through the outer peripheral portion of the seal member SP and engages with the connection enlarged diameter portion 37d, and the engagement hole 39c engages with the engagement claw 39a. Hits the positioning step 38a. As a result, the connected portion 38 is fitted into the connecting portion 37 and the sealing member SP is pressed by the inner wall of the connected portion 38 in a state where the engaging mechanism 39 is engaged.

  Returning to FIG. 3, the lower case support 40 has a cup shape surrounded by the side wall 41 and the bottom wall 42, and is housed in the valve chamber 20 </ b> S of the casing body 30. The float mechanism 60 is supported via 70. A flange 41a projects from the upper portion of the side wall portion 41 in the radial direction, and an upper joint portion 41b is formed upward from the outer peripheral portion of the flange 41a. The upper joint portion 41 b supports the upper opening of the case lower support body 40 so as to cover the case upper lid 45. The side wall 41 forms a ventilation path between the casing body 30 and a part of the outer periphery of the valve chamber 20 </ b> S so as not to raise the float mechanism 60 with the rising airflow.

  The case upper lid 45 includes an umbrella-shaped upper lid main body 45a, a central portion of which is a connection passage 45b, and a lower peripheral edge of the opening is a seal portion 45c. Moreover, the opening peripheral part of the upper part of the connection channel | path 45b is the barrier 45d for returning a fuel. Furthermore, the outer peripheral end of the upper lid main body 45 a is a holding end 45 e and is formed so as to be fitted to the fitting portion 31 b of the casing main body 30.

  The lid body 50 includes a lid body 51, a tube body portion 52 projecting laterally from the center of the lid body 51, and a flange 53 formed on the outer periphery of the lid body 51, and these are integrally formed. . A tube passage 52a is formed in the tube body portion 52. One end of the tube passage 52a is connected to the valve chamber 20S through the connection passage 45b, and the other end is connected to the canister (not shown). An inner welded portion 51a that is welded to the flange 31a of the casing body 30 is formed on the inner peripheral side of the lower portion of the lid body 51, and a lower end portion of the flange 53 is welded to the tank upper wall FTa of the fuel tank FT. A welded portion 53a is formed.

  FIG. 8 is an exploded cross-sectional view of the float mechanism 60. The float mechanism 60 includes a float 61 and an upper float 65 disposed on the top of the float 61. The float 61 includes a float main body 62 having a buoyancy chamber 61S opened downward, and a flange 63 for preventing an upper float 65 projecting from the upper portion of the float main body 62 from coming off. A valve portion 61 a protrudes from the center upper portion of the float 61. A guide protrusion 62 a is formed on the lower outer periphery of the float body 62. The guide protrusions 62a are provided on the side wall of the float main body 62 so as to protrude in eight ribs at equal intervals in the circumferential direction and in a rib shape in the vertical direction. The float 61 is supported by a spring 70 (FIG. 3) spanned between the bottom wall portion 42 and the upper surface of the buoyancy chamber 61S.

  The upper float 65 is a valve for improving the restart valve characteristic, and is supported on the upper part of the float 61 so as to be movable up and down. A communication hole 65b that is opened and closed by the valve portion 61a is formed in the center of the disc 65a. ing. The lower end of the communication hole 65b is a seal portion 65c. In addition, an engaging claw 65d that engages with the outer peripheral portion of the flange portion 63 projects from the lower end of the outer periphery of the disc 65a. A rubber valve element 67 is mounted on the upper float 65, and the valve element 67 is attached to and detached from the seal portion 45c (FIG. 3).

(3) Operation of the fuel cutoff valve 10 Next, the operation of the fuel cutoff valve 10 will be described. As shown in FIG. 1, when fuel is supplied into the fuel tank FT by refueling, the fuel vapor accumulated in the upper part of the fuel tank FT as shown in FIG. It enters into the valve chamber 20S through the bent pipe 32 and escapes from the valve chamber 20S to the canister side through the connection passage 45b and the pipe passage 52a. When the fuel liquid level in the fuel tank FT reaches the predetermined liquid level FL1, the fuel closes the introduction opening 34c, thereby increasing the tank internal pressure in the fuel tank FT. When the sensor detects the increase in the tank internal pressure, an auto-stop functioning to stop the fueling of the fueling gun is activated. In this state, the differential pressure between the tank internal pressure and the pressure in the valve chamber 20S increases, and the fuel flows into the valve chamber 20S through the bent pipe 32 and the communication hole 42a. Then, as shown in FIG. 9, when the fuel level in the valve chamber 20S reaches the height h1, the upward force due to the buoyancy of the float 61 and the load of the spring 70, and the downward force due to the dead weight of the float 61 and the upper float 65 When the former exceeds the latter, the float 61 and the upper float 65 are lifted together, and the valve body 67 is seated on the seal portion 45c to close the connection passage 45b. Thereby, at the time of refueling to the fuel tank FT, it is possible to escape the fuel vapor from the fuel tank FT and to prevent the fuel from flowing out of the fuel tank FT.

  On the other hand, when the fuel level in the fuel tank FT decreases and the fuel in the valve chamber 20S is discharged through the bent pipe 32, the float 61 descends with its buoyancy reduced. The communication hole 65b is opened away from the seat 65c. Due to the communication of the communication hole 65b, the pressure below the upper float 65 becomes almost the same pressure as that in the vicinity of the connection passage 45b, so that the force for closing the upper float 65 is reduced, and the flange 63 is engaged with the engagement claw 65d. By engaging, the upper float 65 is pulled down, the valve body 67 is separated from the seal portion 45c, and the connection passage 45b is opened. Thus, by setting the passage area of the communication hole 65b to be smaller than the passage area of the connection passage 45b, the upper float 65 opens with a small force. Such a two-stage valve structure using the upper float 65 functions to promote the improvement of the restart valve characteristics.

(4) Operation / Effect of Fuel Shutoff Valve 10 The fuel cutoff valve 10 according to the above embodiment provides the following operational effects.
(4) -1 Since the bent tube 32 is formed by being divided into the connecting tube 33 and the introducing tube 34, a molding die for injection molding can be simplified. In addition, if the connection portion 38 is inserted toward the connection portion 37 with the introduction opening 34c of the introduction pipe 34 facing downward, the inner wall of the connection portion 38 passes through the outer peripheral portion of the seal member SP, and the connection enlarged diameter portion The engaging hole 39c is engaged with the engaging claw 39a, and the connecting tip surface 37e of the connecting portion 37 hits the positioning step portion 38a, that is, the connecting tip surface 37e and the positioning step portion 38a pass. The connected portion 38 is fitted to the connecting portion 37 when the surfaces are parallel, and the introduction tube 34 can be easily connected to the connecting tube 33 in a state where the engaging mechanism 39 is engaged. At this time, the plane on which the connecting tip surface 37e of the connecting portion 37 abuts the positioning step portion 38a of the connected portion 38 is not orthogonal to the axis of the introducing tube 34. When inserted in the opposite direction, the engagement hole 39c does not reach the position where it engages with the engagement claw 39a. For example, as shown in FIG. 10, when the introduction tube 34 is rotated by 180 ° and the introduction opening 34c is to be assembled at a position facing upward, the connection tip surface 37e of the connection portion 37 hits the positioning step portion 38a. The engaging hole 39c cannot engage with the engaging claw 39a. Therefore, the introduction pipe 34 is not assembled in the wrong direction to the connecting portion 37, and the setting of the full tank liquid level due to the wrong installation is not caused.

(4) -2 As shown in FIG. 5, since the expansion pipe 38d of the connected part 38 is formed so as to spread toward the tip, the insertion workability is excellent, and the inner diameter of the straight pipe part 38c is Since the outer diameter of the seal member SP is larger and the distance is shorter, the rubber seal member SP is placed on the inner wall of the connected portion 38 with a strong force and longer distance when the connected portion 38 is inserted into the connected portion 37. The seal member SP is not scratched, so that the sealing performance is not deteriorated.

(4) -3 The straight pipe portion 38c of the connected portion 38 has a cylindrical shape and can press the seal member SP uniformly, that is, it does not press on the inclined surface, so that excellent sealing performance can be obtained. .

(4) -4 Since the connection enlarged diameter portion 37d of the connection portion 37 increases the axial distance from the seal member SP to the inner wall on the distal end side of the connection portion 38, the connection portion 38 is connected. The tube 33 is firmly fitted to the tube 33, and the tilt and backlash can be reduced. Therefore, the fluctuation of the position of the introduction opening 34c due to the backlash of the introduction pipe 34 is eliminated, and a stable full liquid level can be obtained.

(4) -5 The connection enlarged diameter portion 37d of the connection portion 37 is provided at a position that increases the axial distance from the seal member SP, but between the connection distal end portion 37a and the connection enlarged diameter portion 37d. Since the annular recess 37c is formed, the inner wall of the connected portion 38 is formed by the annular recess 37c even if the fitting dimensions of the connecting tip portion 37a and the connection enlarged diameter portion 37d and the connected portion 38 are reduced. The contact area is small, the connected portion 38 can be easily fitted to the connecting portion 37, and sink marks that are likely to occur when the connection enlarged diameter portion 37d and the connecting tip portion 37a are formed continuously are formed. Can be prevented.

  The present invention is not limited to the above-described embodiments, and can be implemented in various modes without departing from the scope of the invention. For example, as shown in FIG. 11, the connected portion 38B constituting the connection mechanism 35B forms a single stepped portion 38Ba with respect to the tube main body 34Ba, and has a shape that gradually increases in diameter toward the tip. The shape of the mold may be simplified.

It is sectional drawing which shows the fuel tank of the motor vehicle carrying the fuel cutoff valve concerning one Example of this invention. FIG. 2 is an enlarged cross-sectional view of the vicinity of a fuel cutoff valve in FIG. 1. It is sectional drawing which decomposed | disassembled the fuel cutoff valve. It is sectional drawing to which the vicinity of the introductory pipe line of FIG. 3 was expanded. It is sectional drawing to which the vicinity of the connection mechanism of FIG. 4 was expanded. It is a side view which shows the vicinity of the engagement mechanism of an introduction pipe line. FIG. 7 is a cross-sectional view taken along line 7-7 in FIG. It is sectional drawing which decomposed | disassembled the float mechanism. It is explanatory drawing explaining operation | movement of a fuel cutoff valve. It is explanatory drawing explaining the effect | action of an introductory conduit. It is explanatory drawing explaining the connection mechanism concerning another Example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Fuel cutoff valve 20 ... Casing 20S ... Valve chamber 30 ... Casing main body 31 ... Side wall part 31a ... Flange 31b ... Fitting part 32 ... Bending pipe 33. .. Connecting pipe 33a ... Reduced diameter part 33b ... Vertical part 33c ... Inclined part 34 ... Introducing pipe 34a ... Pipe body 34b ... Bent pipe 34c ... Introducing opening 34Ba .. Pipe body 35 ... Connection mechanism 35B ... Connection mechanism 36 ... Fitting mechanism 37 ... Connection portion 37a ... Connection tip 37b ... Seal recess 37c ... Annular recess 37d ... Connection expansion part 37e ... Connection tip surface 38 ... Connected part 38B ... Connected part 38a ... Positioning step part 38b ... Step difference 38c ... Straight pipe part 38d. .Expansion pipe 38Ba ... Step part 39 ... engaging mechanism 39a ... engaging claw 39b ... engaging piece 39c ... engaging hole 40 ... case lower support 41 ... side wall Part 41a ... Flange 41b ... Upper joint part 42 ... Bottom wall part 42a ... Communication hole 45 ... Case upper lid 45a ... Upper lid body 45b ... Connection passage 45c ... Seal 45d ... Wall 45e ... Holding end 50 ... Ladder 51 ... Lid body 51a .. Inner welded part 52 ... Tube part 52a ... Pipe passage 53 ... Flange 53a ... Welded part 60 ... Float mechanism 61 ... Float 61S ... Buoyant chamber 61a ... Valve Part 62 ... Float body 62a ... Guide protrusion 63 ... Bridge 65 ... Upper float 65a ... Disc 65b ... Communication hole 65c ... Seal part 65d ... Engagement Claw 67 ... Valve 70 ... Spring SP ... Sealing member FT ... Fuel tank FTa ... Tank upper wall FTb ... Mounting hole FTSa ... Tank space FTSb ... Tank space FTSc ... connection space

Claims (6)

A fuel cutoff valve that is mounted on the upper part of the fuel tank (FT) and that opens and closes a connection passage (45b) that connects the inside of the fuel tank (FT) and the outside, thereby disconnecting the fuel tank (FT) from the outside passage. ,
A casing body (30) that forms a valve chamber (20S) that connects the connection passage (45b) and the inside of the fuel tank (FT), and a lower part of the casing body (30) that is provided in the fuel tank (FT). A casing (20) having an introduction opening (34c) for introducing fuel and a bent pipe (32) leading from the introduction opening (34c) to the valve chamber (20S);
A float mechanism (60) having a valve portion which is housed in the valve chamber (20S) and moves up and down by increasing or decreasing buoyancy according to the fuel liquid level in the valve chamber (20S) and opens and closes the connection passage (45b);
When the fuel level reaches the fuel level that closes the introduction opening (34c), the fuel is led to the valve chamber (20S) through the bent pipe (32), and the float (61) is raised. Configured to close the connection passageway (45b),
The bent pipe (32) is arranged at a lower portion of the casing body (30) so as to be obliquely downward with respect to the vertical direction, and connected to the valve chamber (20S). 33) and an introduction pipe (34) having the introduction opening (34c), and a connection mechanism (35) for connecting the connection pipe (33) and the introduction pipe (34),
The connection mechanism (35) includes a connection portion (37) formed at an outer peripheral end portion of the connection pipe (33) and an outer fit of the connection portion (37) formed at an end portion of the introduction pipe (34). The coupling mechanism (36) having the connected portion (38) to be connected, the connecting pipe (33), and the connected portion (38) are formed and engaged with each other to thereby connect the connecting pipe (33). An engagement mechanism (39) for connecting the connected portion (38), and a seal member (SP) interposed between the outer peripheral portion of the connecting portion (37) and the inner peripheral portion of the connecting portion (37). And
The fitting mechanism (36) includes a positioning step portion (38a) that is formed on the connected portion (38) and that positions the connecting tip surface (37e) at the tip of the connecting portion (37) by abutment. A plane passing through the connection tip surface (37e) and the positioning step (38a) is non-orthogonal to the axis of the introduction pipe (34), and the connection tip surface (37e) and the positioning step (38a) are parallel. The engagement mechanism (39) is configured to be engageable when
A fuel shut-off valve characterized by The fuel cutoff valve according to claim 1, wherein
The outer peripheral portion of the connection portion (37) has a connection tip portion (37a), a seal recess (37b) for holding the seal member (SP), and a connection expansion having a larger outer diameter than the connection tip portion (37a). A diameter portion (37d) is provided from the distal end side of the connecting portion (37) toward the casing body (30) side, and the connected portion (38) has the distal end of the connected portion (38) sealed by the seal. A fuel cutoff valve whose outer diameter is wider than the sealing surface of the member (SP).
Fuel shut-off valve. The fuel cutoff valve according to claim 2,
A fuel cutoff valve in which the diameter of the connected portion (38) is gradually increased toward the tip of the connected portion (38). The fuel cutoff valve according to claim 1, wherein
The connected portion (38) includes a straight pipe portion (38c) having an inner wall of the same outer diameter that seals the sealing member (SP) by pressing, and the connected portion (38) from the straight pipe portion (38c). The fuel shut-off valve provided with an expansion pipe (38d) whose diameter is expanded toward the tip end side of). The fuel cutoff valve according to claim 2,
A part of the outer peripheral portion of the connecting portion (37) has a small diameter so as not to contact the inner wall of the connected portion (38) between the connecting enlarged diameter portion (37d) and the seal recess (37b). A fuel cutoff valve in which an annular recess (37c) is formed. The fuel cutoff valve according to any one of claims 1 to 5,
The engagement mechanism (39) is engaged with the engagement claw (39a) formed at the end of the engagement claw (39a) formed at the connection portion (37) and the connected portion (38). And a fuel cutoff valve provided with an engaging hole (39c).

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